NASHUA , New Hampshire -LRB- CNN -RRB- -- The economy in southern New Hampshire is not by any means among the worst in the nation . Still , according to city records , there are 29 foreclosed homes on the books in Nashua -- many of which are in deplorable condition .

Walls had been ripped open in this foreclosed home in Atlanta , Georgia .

`` This house is not livable right now , '' Nelson Ortega , the city 's chief building code inspector , told CNN as he stood in front of a boarded-up single-family home on a residential street in Nashua .

The foundation of the house was fractured , Ortega said , and there were cracks and fissures in many of the supporting beams . At the side entrance to the house were broken windows , garbage and peeling paint .

In 2006 , Ortega said , the property sold for $ 200,000 . It 's anyone 's guess , he said , what price the home might bring now , if it ever sold .

That this foreclosed home might not ever sell was not news to a researcher who lives nearby .

`` About a third of all of the foreclosed properties nationwide have been so damaged , either by the previous owners or by criminal gangs coming in after the foreclosure , that they no longer qualify for standard mortgage financing , '' Thomas Popik told CNN . `` So there is going to be all kinds of government programs to help , but if they do n't qualify for standard mortgage financing , there 's no one to buy these properties . ''

Popik says responses from thousands of real estate agents nationwide to the questionnaires he sends out quarterly indicate that badly damaged foreclosed homes -- so-called `` distressed '' properties in real estate jargon -- are a much bigger element of the national housing picture than officials in Washington have acknowledged .

Popik 's work is under the auspices of Campbell Communications , a Washington-based group that supplies data to private mortgage industry analysts .

`` In many cases , it costs so much to rehabilitate these houses , it 's just not cost-effective , '' he told CNN . `` And the properties are eventually going to be bulldozed . ''

In some cities hit harder by the national economic downturn , a quick glance at foreclosed homes paints an even harsher picture .

`` A lot of these homes have been vandalized , '' Dana Ash , an Atlanta , Georgia , real estate broker , told CNN . She was speaking in front of several foreclosed , boarded-up houses not far from the city 's center .

`` They are a little scary going into them , '' she said . `` The power is out , a lot of them are boarded up . ''

A CNN camera crew was allowed into several of the houses . Trash was everywhere ; plaster walls had been ripped open to expose wiring ; and in one case a toilet was dumped on an empty living room floor .

The banks that own the properties , Ash told CNN , probably will not simply walk away from the homes .

`` Usually abandoning homes means it has n't sold , '' she explained . `` They will eventually sell . It will be pennies at best on the dollar , but they will eventually sell . ''

From his office in New Hampshire , Popik said he is not at all certain of that .

`` There are some cases where the properties have been so damaged that it 's not profitable for the mortgage investor , which is a bank , to take title to the property , '' he said .

The Mortgage Bankers Association told CNN it found no hard evidence of such a trend . Some of the information , a spokesman said , was `` anecdotal , '' but there was no data one way or the other yet collected .

A spokesman for the Department of Housing and Urban Development in Washington told CNN that unsalable homes are still a relatively small part of the national inventory of foreclosed properties . But , the spokesman added , the worse the economy is in a particular region , the more damaged and vandalized foreclosed homes are likely to be .

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Many foreclosed homes are so damaged , they probably wo n't be sold , some say

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Researcher : One-third of foreclosed homes too damaged for standard financing

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Many of the houses are `` eventually going to be bulldozed , '' researcher says

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Mortgage Bankers Association says it has no hard evidence of such a trend